document.write( "Question 560291: The area of a grassy plot is 480 metres. If each side had been 5m longer, the area would have been increased by 245 square metres. Find the length of the fence to surround it. \n" ); document.write( "
Algebra.Com's Answer #363824 by mananth(16946)![]() ![]() You can put this solution on YOUR website! let the length be x \n" ); document.write( "width = y\r \n" ); document.write( "\n" ); document.write( "xy=480 \n" ); document.write( "x=480/y\r \n" ); document.write( "\n" ); document.write( "(x+5)(y+5) is the area after increasing the sides\r \n" ); document.write( "\n" ); document.write( "xy+5x+5y+25\r \n" ); document.write( "\n" ); document.write( "xy+5x+5y+25- xy = 245\r \n" ); document.write( "\n" ); document.write( "5x+5y=245-25 \n" ); document.write( "5x+5y=225 \n" ); document.write( "x+y=45 \n" ); document.write( "480/y +y = 45\r \n" ); document.write( "\n" ); document.write( "multiply equation by y \n" ); document.write( "480 +y^2=45y \n" ); document.write( "y^2-45y+480=0\r \n" ); document.write( "\n" ); document.write( "Find the roots of the equation by quadratic formula \n" ); document.write( " \n" ); document.write( "a= 1 , b= -45 , c= 480 \n" ); document.write( " \n" ); document.write( "b^2-4ac= 2025 + -1920 \n" ); document.write( "b^2-4ac= 105 \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "x1=( 45 + 10.25 )/ 2 \n" ); document.write( "x1= 27.62 \n" ); document.write( "x2=( 45 -10.25 ) / 2 \n" ); document.write( "x2= 17.38\r \n" ); document.write( "\n" ); document.write( "sides are 27.62 & 17.38m\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "The Perimeter=2*( 27.62 + 17.38)\r \n" ); document.write( "\n" ); document.write( "= 90 meters \n" ); document.write( " |